
Troubleshooting (Qualified Servicer Only)
15
PRIMARY CIRCUIT
If there is supply line voltage at the service connections
and no input voltage to the power supply (green light out),
the outage can be located by checking operation of the
safety switch and the interconnecting wiring with a multim-
eter. Refer to circuit diagram (Figure 16) to check opera-
tion of the switches. Follow these steps:
1. Ensure air cleaner circuit breaker is in the ON posi-
tion and fuse is not open.
2. The power supply board has a built-in internal fuse
to protect the 24V transformer. It can be checked vi-
sually by inspecting the fuse. If the fine wire inside
the fuse is broken, a problem exists in the 24V circuit
of the power supply board. Do NOT replace this
fuse. The entire power supply board must be re-
placed. The purpose of the fuse is not to protect the
power supply board, but to function as a trouble-
shooting feature of the product to protect the trans-
former from damage.
3. If the fuse is NOT blown, check the ON/OFF switch
and safety interlock switch for proper engagement
and operation. This can be completed using a volt-
ohm multimeter.
4. Check the ON/OFF switch and wiring. Disconnect
wire between ON/OFF switch and power supply from
the power supply. Disconnect wire between the ON/
OFF switch and safety interlock switch at the safety
interlock switch. Connect a multimeter to discon-
nected wires. Turn the ON/OFF switch to the ON po-
sition. The meter should indicate a continuous
circuit. If multimeter indicates an open circuit, check
each wire and switch to determine which component
is open. Repair or replace as needed.
5. Check the safety interlock switch and wiring. Dis-
connect wire between safety interlock switch and
power supply from the power supply. Disconnect
wire between the safety interlock switch and ON/
OFF switch at the safety interlock switch. Connect a
multimeter to the safety interlock switch and discon-
nected wire. Depress the safety interlock switch.
The meter should indicate a continuous circuit. If
multimeter indicates an open circuit, check wiring
and switch to determine which component is open.
Repair or replace as needed.
SECONDARY CIRCUIT
WARNING
PERSONAL INJURY HAZARD
The following procedures will expose hazardous live
parts. Disconnect power before proceeding and
between checks. Failure to do so could result in
severe personal injury or death.
A short circuit can develop if the space between the
conductive or semi-conductive material is bridged. The
bridging or short may be caused by damaged components,
improper voltage or foreign material lodged between or on
the components.
To check the secondary circuit for proper output voltages:
1. Remove power tray access cover and door panel.
2. Visually inspect. Ensure the system blower is oper-
ating, the control switch is ON and, using a multim-
eter and probe, input voltage is as specified.
Also check the cell contacts and high voltage contact
board assembly for corrosion, excessive dirt build
up, and electrical arc tracking (carbon path from
stainless steel spring to grounded metal). If corro-
sion, build up, and or arcing is present, clean or re-
place contact.
3. Make connections from the high voltage probe to the
multimeter in accordance to the operator’s manual.
The meter should be set for reading DC voltage at a
20-volt full scale.
4. Remove the cell access door. Attach the high volt-
age ground lead from the high voltage probe to the
cabinet. While depressing the safety interlock
switch, touch the ionizer wire support bar with the
end of the high voltage probe (see
Cell Trouble-
shooting Chart
). The meter should read 6.2 kVDC
±0.2 kVDC.
5. If no voltage is measured, remove the first cell and
check the second cell. The meter should read 6.2
kVDC ± 0.2 kVDC.
6. If proper voltage is measured, the first cell is shorted